Hello,
something that slowly and surely drives me crazy on the new CD35C combi boiler from Alpha- any thoughts highly appreciated, as this was observed for weeks and weeks now:
1. We start with pressure gauge showing 1 bar, in middle of green area on the display.
2. If the system had long periods of no heating AND no hot water use (1/2 to 1-2 days time period when nobody home), the gauge seems to indicate a loss of pressure of up to 0.2 bar.
3. However, it is enough to then have a shower (hence only using hot water, NOTHING moves on heating front) and the needle goes up by quite noticeable amount (even 0.1 or more bar).
4. One can actually see that after hot water usage stopped, it makes some humming noises for a few seconds and as soon as that stops, the needle jumps up a bit then stays at this slightly higher value. These 'bits' are cumulative, and if then left alone again for 1/2 day or more, it can go down again. If frequent hot water use, NO heating, the needle can go back to pretty much where it started...
Initially I thought I'm losing pressure, as it can over time drop, but then why would it correct itself to some (or full) extent just because hot water was used...
One can not dismiss the possibility of a very subtle leak in CH system, BUT the pressure being "lost" gradually when it is NOT in ANY use, then actually increasing pressure indication while heating has NOT come on (only hot water), makes me seriously question actual leak.
Any ideas? has anyone observed this on Alpha boilers or whatever makes? is there some (intended or faulty) connection between the heating and hot water systems, some leak in expansion tank (but affected by hot water usage?!) or something - or plain inaccuracy of the gauge?
It can really drive one paranoid about some subtle leak in heating system, but... bizarre contrary behaviour observed.
Many thanks in advance.
something that slowly and surely drives me crazy on the new CD35C combi boiler from Alpha- any thoughts highly appreciated, as this was observed for weeks and weeks now:
1. We start with pressure gauge showing 1 bar, in middle of green area on the display.
2. If the system had long periods of no heating AND no hot water use (1/2 to 1-2 days time period when nobody home), the gauge seems to indicate a loss of pressure of up to 0.2 bar.
3. However, it is enough to then have a shower (hence only using hot water, NOTHING moves on heating front) and the needle goes up by quite noticeable amount (even 0.1 or more bar).
4. One can actually see that after hot water usage stopped, it makes some humming noises for a few seconds and as soon as that stops, the needle jumps up a bit then stays at this slightly higher value. These 'bits' are cumulative, and if then left alone again for 1/2 day or more, it can go down again. If frequent hot water use, NO heating, the needle can go back to pretty much where it started...
Initially I thought I'm losing pressure, as it can over time drop, but then why would it correct itself to some (or full) extent just because hot water was used...
One can not dismiss the possibility of a very subtle leak in CH system, BUT the pressure being "lost" gradually when it is NOT in ANY use, then actually increasing pressure indication while heating has NOT come on (only hot water), makes me seriously question actual leak.
Any ideas? has anyone observed this on Alpha boilers or whatever makes? is there some (intended or faulty) connection between the heating and hot water systems, some leak in expansion tank (but affected by hot water usage?!) or something - or plain inaccuracy of the gauge?
It can really drive one paranoid about some subtle leak in heating system, but... bizarre contrary behaviour observed.
Many thanks in advance.
